Heat shouldn't, but Defrost will.
The front defrost/defogger uses the AC. This is why it hurts MPG. It is a necessary evil sometimes, though.

 

Good on all points and we all have different tricks to our own unique drive and commute and keeping warm and such so it is hard to make a blanket statement sometimes. Most times when I need to clear the windshield I will click the Defroster button but then tap the A/C button to turn OFF the A/C but still keep warm air on the windshield and this gets the best of both worlds.

Leah - try and get all of your previous fill-ups entered into the Database at some point. This is not so much for you but for all the rest of us. If there is a potential owner in Chicago then I'm sure they want to see the real-world numbers from lots of folks in Chicago.

 

As I'm still new at this, I don't have a block heater yet, and I'm not sure if I should get one. Here in Colorado, we're still dealing with sub-freezing temps - yesterday, my car registered a high of 1 degree F while on my morning drive to work. At any rate, the whole 11.1 mile drive to work for me did not show any Auto Stop process. Yet on the way home, when it warmed up to about 23 degrees, I actually had a few instances when just about 2 to 3 miles down the road, I was getting the Auto Stop from then on at most lights.

I'm not sure how warm the car has to be or if the Auto Stop has to work at certain temps alone, but I'm doing well. Throughout the day, too, I maintained around 40mpg. I was really worried about it, but the car seems to be holding its own quite nicely. Only on my 2nd tank now and have driven about 650 miles (first tank and my first go at this gave me 426 miles).

Peter

 

I recently switched from driving 250 miles a day to driving 20.... 10 to work, 10 back. On my commute, with the temp around 17-26 the last week, I got about 34mpg on the 17 degree days, and about 40 on the 26 degree days. On the colder days, I get my first autostop around half a mile from work, and even then, it only stays stopped for about 30 seconds before kicking on. It's just not enough time to warm up. I also don't have a garage (just a car-port) right now, so it starts from dead cold.

Today, I don't anticipate my engine warming up at all...I'll be happy to get over 30mpg today....it's 1 degree F and it's not getting any warmer.

 

OMG, I am down to 36mpg! Temps in single digits.

 

Look, I know that the database is useful and that it's helpful to see or hear about other people's real-world results. That's why I post here. That's why I've been posting here for so long (practically a year longer than you, as it happens). But I decided long ago to stop posting to the database after my first few tanks. Sorry. Mostly I was afraid I'd be tempted to fudge my results- that darn competitive streak!- but anyway, I decided.

Someday I'll go through that drawer and look at my data. I like data! That's why I keep the receipts. I know it won't be complete- it's not the world's greatest organizational system, as you can guess, and I'm certain I'll be missing some receipts or other info. At this point it's been so long that it'll be a pain to straighten it all out, but it should be amusing once I actually have the data set to graph and chart everything. Then I may even post about it. Until then, I'm going to keep using my tripmeters the way I have them- even without the first digit, the overall lifetime readout is still perfectly useful, and at least I have some total figure. Otherwise one missing receipt could mess it all up.

 

I swear my posts are falling on deaf ears sometimes. We finally had the cold temps I was expecting back in Dec (single digits with snow) so I'm getting the lower FE numbers I was anticipating for the last two months - so am not disappointed to see them though they are depressing sometimes. Anyway, I was able to do another half-commute (the one mostly downhill and 80% Interstate that I posted earlier) to match all the other test drives. The results are below for my segments today.

02/05, Trip 1 = 07.2 mi total @ 45.4 mpg and 7 F
02/05, Trip 2 = 29.6 mi total @ 39.7 mpg and 8 F
02/05, Trip 3 = 48.0 mi total @ 40.5 mpg and 8 F (end of the day at home)

This is only 3 mpg lower than when the temps were 20-30 F (the first trip). I was amazed. I can usually AutoStop after 1.5 miles from home (temp at 9 blocks) but I'll admit though that today the car never got to 9 blocks of warmth even toward the end of the 7.2-mile drive so it never got to AutoStop or get to EV mode today and still got 45 mpg in the cold. I don't have a garage or carport and the car sits out uncovered nightly with only the Block Heater plugged in. I will say that with temps at 8 F it is a big difference to the 18 F it was last week as the car would AutoStop in normal time before but today it definitely was colder to the car. My car didn't really warm up either (and the first trip isn't typical for the day as it is mostly downhill but I listed all three segments for today).

From 38 F to 28 F it was not a big change. From 28 F to 18 F it was not a big change. From 18 F to 8 F made a world of difference. I was asking our pals to the North what the deciding temps were or if the Block Heater made a difference but I've found that for me it is around 10-15 F as anything lower takes some concentration or a little time to warm up initially. I will say that the Block Heater makes a big difference though. It might not pay for itself but it is fun to be near practically-normal operating mods (staying in AutoStop for 2 and 3 minutes at a time, heat from the vents within a mile from home, yadda, yadda, yadda). Everyone is welcome to borrow my car for their chilly commute if you want. <smirk>

 

Leah - So what is your lifetime average mpg on your car and how long have you owned it and what is the total mileage? I've owned mine since August so this low FE bout really drags me down but once I have another half-summer to complete my one-year then I'll be able to bring the average back up (whereas if I bought it in Nov then I wouldn't have had a high average which is now a mediocre average but it would have been 45 mpg down to 43 mpg but would rise once I get through the summer).

Or - what were other results of folks at their 1-year anniversary? I think our cars came out in Nov '05 so a small slice of us have actually had their car for over 1 year. I'm looking forward to the Spring and Summer to bring up the average to over (hopefully) 51 mpg.

 

Agreed. We had a few weeks at 7-15 degrees. That tank ended yesterday at 36.9mpg!! Since then the temps have steady risen (around 20 deg) and I am back at ~42mpg.

Phew!

 

My lifetime average just (a tank ago) dropped from 48.8 mpg to 48.4.
It's the weather. Urk. I bought it in August 2005, and there are a few more than 20,000 miles on it.

I've got about 45 mpg this morning, after a miserable tank at 41.2. Practically my worst ever! The worst ever was 38.9mpg- NOT my fault, my mom was driving, heavily loaded, at about 80 mph in high winds and sub-freezing temps on a highway with every accessory blasting away. This latest disaster tank included about 130 miles of my dad driving on a highway at about -10 degrees, -25 windchill. Letting a parent drive can sometimes be a big mistake- but in this weather, I'd rather my dad drove my car instead of his '94 station wagon (due to die any day now) so he doesn't risk being stuck by the side of the road in the cold. Besides, even if it hurts my numbers, I'm still saving gas overall- his car only gets 18 mpg to begin with- probably more like 10 in this weather.